GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Column/Ignition Lock Schematics

Connector End View Reference: Steering Wheel and Column Connector End Views

1

Did you review the Steering Wheel and Column description and operation and perform the necessary inspections?

Go to Step 2

Go to Steering Wheel and Column Description and Operation

2

  1. Push the ignition lock cylinder control actuator release button which is on the underside of the ignition key cylinder.
  2. Turn the key to the OFF position and remove the key.

Were you able to turn the key to the OFF position and remove the key?

Go to Step 3

Go to Lock System Does Not Lock

3

Verify the fault is present.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the ignition lock cylinder control actuator.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage and ground circuits of the ignition lock cylinder control actuator.
  5. Cycle the gear shift from Park to Drive.

Does the test lamp turn ON and OFF with each cycle?

Go to Step 12

Go to Step 5

5

Connect a test lamp between the ground circuit of the ignition lock cylinder control actuator and B+ voltage.

Does the test lamp illuminate?

Go to Step 6

Go to Step 8

6

  1. Turn OFF the ignition.
  2. Reconnect the ignition lock cylinder control actuator.
  3. Disconnect the floor shift control connector.
  4. Turn ON the ignition, with the engine OFF.
  5. Connect a test lamp between the battery positive voltage and ground circuits of the park switch.

Does the test lamp illuminate?

Go to Step 11

Go to Step 7

7

Connect a test lamp between battery positive circuit of the ignition lock cylinder control switch and a good ground.

Does the test lamp illuminate?

Go to Step 10

Go to Step 9

8

Repair the open in the ground circuit of the ignition lock cylinder control actuator circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 15

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9

Repair the open or short to ground of the ignition lock cylinder control switch battery positive voltage circuit. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 15

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10

Repair the open, short to ground, or short to voltage of the ignition lock cylinder control switch signal circuit. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 15

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11

Inspect for poor connections at the ignition lock cylinder control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 13

12

Inspect for poor connections at the ignition lock cylinder control actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

13

Replace the floor shifter. Refer to Transmission Control Replacement .

Did you complete the replacement?

Go to Step 15

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14

Replace the ignition lock cylinder control actuator.

Did you complete the replacement?

Go to Step 15

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15

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 4